Method and means for ventilating enclosures



Patented Dec. 13, 1938 PATENT OFFICE METHOD AND MEAN S FOR VENTILATING ENCLOSURES Karl D. Perkins, Providence, R. I.

Application June 19, '1935, Serial No. 27,345

2 Claims. (01. 98-1) This invention relates to the ventilation of enclosed spaces. It is the teaching and practice of the leading authorities on air circulation in occupied rooms that there must be a general movement of air through the occupied spaces and that the air must be turbulent. are two general methods; (a) to put large continuous streams of air-into the rooms through many outlets, at as ldw a velocity as will produce a gentle turbulence and a general circulation in the air of the room, and (b) to put into the room smaller continuous streams of air at high velocity through a few nozzles or jets directed across the open spaces in the upper part of the room, causing general circulation of air and much turbulence. Using one of these two methods or a combination of them, those highly skilled in the art are able to design and put into successful operation circulating systems which give excellent results, particularly in large rooms in new buildings which have large supply andexhaust ducts built into the walls where required. But there are distinct limitations to what may be accomplished by these methods, because every continuous stream of air flowing at sufiicient velocity to cause the necessary turbulence, also causes induced currents and drafts in the air of the room which are quite beyond control, and there are often dead spaces without either circulation or turbulence. The diiliculty is inherent in the nature of the air itself and in the effect of continuous currents fiowing through it.

This invention provides a method and apparatus for producing and controlling discontinuous currents of air which flow through a room without causing eddy currents, and may be used to set up turbulence at any spot in the room without interfering with the gentle flow of air through it. These discontinuous currents have properties and characteristics as different from those of continuous currents, as an alternating current of electricity difiers from a direct current.

Such alternating air currents consist of an interrupted series of projectiles of air shot into a room from an orifice or a nozzle or a duct. The pressure or velocity at which the stream of projectiles moves is equivalent to the voltage. The quantity of air flowing in the stream is the amperage. The number of projectiles per second is the number of cycles. There are many other phenomena similar to those caused by the passage of electric currents, such as resistance, induced currents, opposite polarities,

To accomplish this, there.

attraction and repulsion, etc., which are available under control to produce and to maintain exactly the conditions which are required in all parts of a room.

The movement of one of these projectiles. through the air of a room may be as smooth and undlsturbing as desired. 'A-current of projectiles, 3 each three times as long asits diameter will glide through the air because it mushrooms out, on leaving the orifice, and forms a streamlined shape which allows the air which it displaces in front to fiow quietly in behind it leaving scarcelya ripple.

There is no limit to the size of the orifices which may be used except the limitations of space in which to house them and space for the ducts to supply them. Groups of very small orifices may beused alone or in combination with larger orifices, to carry heat and humidity, or cold and dryness to a small locality in a large room. Great flexibility is given to the ventilating system bymounting the orifices so that they may be raised and lowered and swung in any direc-' tion.

In the accompanying drawings:

Figure l is an elevation, partly in section as on line ll of Figure 2;

Figure 2 is a plan, partly in section as on line 2-2 of Figure 1;

Figure 3 is aperspective of the distributor;

Figure 4 is a vertical section through a modified form of apparatus; and

Figure 5 is an elevation, taken as on line 5-5 of Figure 4.

Referring to the drawings and particularly to Figures 1-3, the air to be projected in the space to be treated is received through a duct I from conventional air-conditioning apparatus and driven by impelling means, such as the fan 2, through a duct 3 in which is provided a valve -or damper 4 that oscillates under the control of a motor 5 and suitable connecting linkage. The air then enters the open bottom of a distributor 6 which is rotated by some means such as a motor 7. The top and cylindrical side wall of this distributor are closed except for a vertically extending port 8, and the inner surface of the distributor may be shaped to direct the air fiow generally toward this port. Surrounding the distributor is a casing 9 with openings l0 into a series of pipes or nozzles ll each of which terminates in circular orifices l2. As the distribut'or rotates and its port 8 passes by an opening ill, air is forced into a chamber II' and thence through an orifice l2 into the atmosphere.

. that port 8 and an'opening ID are in register and upon the rate of flow of the air. The former is determined by the relative sizes of the port and opening and the speed of rotation of the distributor, the latter being controlled by the operation of motor 1. The rate of air fiow is determined by the action of the impelling fan 2 and the oscillations of the damper 4.

A slow turning of the distributor 6 with the damper wide open introduces a quantity of air into a nozzle-H such that a pear-shaped projectile of conditioned air will pass 'out of the orifice I! in somewhat the shape suggested at A in Figure 2. This projectile or slugof air has a length greater than the diameter of the orifice and takes a stream-line like shape. It glides easily through the atmosphere of theroom to its destination where it goes to pieces, setting up no eddy currents but causing much turbulence.

Various means may be devised for practicing the method herein disclosed. In Figures 4 and 5 a modified type of apparatus is disclosed. A casing l4 receives conditioned air through a duct I a, and is provided on one side with a series oi nozzles I la. Closely adjacent the inner openings to'these nozzles is a disk 15 having a single opening it therein adapted ,to register successively with the several nozzle openings. This disk is rotated by the relatively slow-speed end of a. motor shaft l1 whose opposite high-speed end 18 carries a fan 19. As the motor 20 rotates the fan builds up a pressure of air on the disk I5 and as the latter rotates and its opening registers with the inner opening of a nozzle, a charge of ,air is introduced into the nozzle and thereafter is projected fromthe orifice 12a, as hereinbefore described.

The hereinbefore mentioned slow turning of the distributor 6 and the relatively slow speed of the disk l5, together with a low velocity of the conditioned air, enables a portion of this air to be discharged as it were in the form of a streamlined projectile. The preconditioned air is not in any sense compressed air, nor indeed is it under any great pressure above atmosphere.

It is necessarily undervery light pressure to give it its very slow velocity, but the projectile issues from the nozzle with a lazy, easy-going, slow motion, just sufflcient to carry the pear-shaped projectile to the region where it breaks up and thereby causes local turbulence. For example,

if the nozzle l2 or I20, is six inches in diameter, the projectile A issuing therefrom should travel, roughly, at the rate of about five feet a second. The rate of rotation of the distributor 6 or the disk l5 should be determined by test to give the aforesaid speed of travel of the projectile.

This alternating current method of ventilation gives flexible control of the separate factors of air movement, air turbulence and air blending. It produces a better result inthe room while handling only half the air required by the. continuouscurrent methods, and since it handles air forty degrees colder than the room air it is possible to maintain a room at a lower humidity content in summer without re-heat. Also, because it is possible by the alternating current method to maintain perfect conditions in a room with only one half of the air movement required by the continuous current methods. there is advantage in the winter season from a greatly reduced general circulation of air- It is unnecessary air circulation which must be guarded against, both in summer and in winter, chiefly as a measure of good health protection, but also because it is destructive to furniture, paintings, rugs, and hangings by drawing the moisture from them. It is rapidly moving humid air which is used to dry out green lumber, not hot still air. After a rain, a good steady wind under a cloudy sky will dry a muddy road in half the time required by hot sunshine in still air.

Many architects, consulting engineers, and ventilating engineers prefer to circulate only fresh outdoor air in a room occupied by persons, but since it is necessary, by the continuous current methods tore-circulate three times as much room air as the outside air required, few installations are made handling outside air only. By cutting in half the total circulation required, the alternating current method now makes it possible for people to enjoy the benefit of an ideal, hundred per cent fresh air ventilating system.

I claim as my invention:

1. The method of ventilating an enclosure which comprises projecting into the atmosphere bination, a nozzle having a converging wall adjacent its opening; means for supplying preconditioned air under slightly greater than atmospheric pressure for discharge through said nozzle; and means for regulating said discharge to cause a streamlined pear-shaped projectile of said preconditioned air to leave said nozzle intermittently. KARL D. PERKINS. 

